On Saturday, Stephanie's parents gave birth to twins and named them Jessica and Luis. When they were first born, Jessica weighed 6.29 pounds, and Luis weighed 8.87 pounds. How much did the babies weigh in total?
Explanation: To find the weights of the 2 babies, we need to add their weights together. Jessica's weight + Luis's weight = total weight. ${6}$ ${2}$ ${9}$ ${8}$ ${8}$ ${7}$ ${+\vphantom{0}}$ ${6}$ ${1}$ ${5}$ ${1}$ Together, the babies weigh 15.16 pounds.